WASHINGTON – A Queens congressman charged yesterday that environmental authorities may have OK’d the anti-mosquito spray malathion because of lobbying by a firm that employs former EPA officials.

The Environmental Protection Agency and the consulting firm both denied the charges.

Democrat Rep. Gary Ackerman claimed the EPA, which recently ruled malathion was safe for spraying West Nile virus-carrying mosquitoes, was influenced by a Virginia consulting firm that employs at least four ex-EPA big-wigs.

“I am not an alarmist, but this is cause for concern,” Ackerman said.

The ex-officials now working for Jellinek, Schwartz & Connolly Inc., which represents the Danish company that makes malathion, include Steven Jellinek, EPA’s former first assistant for pesticides; Edwin Tinsworth, former director of special review for pesticides; Daniel Barolo, who worked for the New York Department of Environmental Conservation and the EPA’s pesticide-program office; and Jeffrey Schwartz, a former EPA lawyer.

“This taints the public confidence in what’s happening,” said Ackerman, who butted heads with feds and city officials over malathion last summer. “It smells fishy to me.”

But Jellinek, who left the EPA in 1981 to start his consulting firm, said Ackerman just insults current EPA workers with the charge.

“Ackerman is just jumping on the bandwagon” with people who oppose malathion, said Jellinek, who called Ackerman’s charges “outrageous” and “nasty,” adding: “We don’t have any undue influence.”

Jellinek’s Arlington, Va., consulting firm helps companies negotiate through the science and environmental bureaucracy of the federal government. He said his staffers, whether they lobby or consult, refrain from contacting their former co-workers in government for at least a year – and in some cases permanently.

“We follow the rules,” he told The Post.

EPA spokeswoman Martha Casey said the agency is not influenced by former staffers who leave government to work in the private sector.

Although Mayor Giuliani decided earlier this year not to spray malathion unless other chemicals fail to work, critics are raising questions about why it was used last year.